Concrete structure.



` No. 893,272. BATENTED JULY 14, 190s.

y 6,13. SPRINGER.

GGNGRETE STRUCTURE;

APPLICATION I ILBD JULY 10. 1905. RBNEWBD MAR. 20. 1907- ggg?? l l -jr 555% i ynarrar) srATEs CHARLES E. SPRINGER, OF CHICAGO, ILLINOIS.

l CONCRETE sTRUc'rURE.

Specification of Lettera Patent.

Patentecg'uly 14, 1908.

. Application filed July 10, 1905, Serial No. 268,943. Renewed March 2Q, 1907. Serial No. 363,367.

To all '1L-hom it vma 1/ vm/cern Be it known that l, CHARLES E. SPRINGER, a citizen of the United States of America, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Concrete Structures, of which the following is a specification. 4

The object of my invention is to provide a reinforcing tension member for concrete slabs and Uirders, and to provide improved mea-ns for tbonding such tension member to the concrete.

In the drawings-Figure 1 is 'a sectional view of al concrete girder reinforced by my improved tension member. Fig, 2 is a transverse section of the same. Fig. 3 is a ers ective view of )art of the tension mem er.

i 4 is a view oi a modified form.

he main body of my'im rov'ed tension member 'consists of a centra web and side ortions of greater thickness than the web. hese side portions may be of the/ form illustrated in Iigs. 2 and 3 or any other suitable form,'such as that shown in Fig. 4.

In order to secure adhesion between me-r tallic tension members and the concrete beams or slabs in which they are embedded it has been custom ary to corrugate the tension members and toprovid'e them with trans-` verse anchor arms extendinginto the concrete. I therefore do not claim broadlythe idea of roviding` a tension member with such anc or arms.

The anchor arms orming part oi my tension member are formed by punching, sawing i balanced directions web se iar'ating. them.

' arms th along the bar. AIt desired the upper endet l .eachnmn may be deiiected outwardly,;as` :shown in the drawing-or inwardly if so deaired-- i `slits at each side of the central lweband by transverse. slits at' one'end of the longitudi" nal slitsl l, 'Ilie anchor arms are arranged in pairs andare beutup in opposite from the .portion of the .central us constitutes a com eteandfindi' vidual vbalanced vpair or U-s aped anchor,

balanced locally and arranged in a series Each )air of anchor,

anchor arms will possess all the advantages of the complete member. As the anchor arms of each pair are symmetrical, and as each pair is like every lother pair, the bars may be manufactured in standard lengths and cutl to suit the requirements of any individual case without incurring loss, or necessitating;t the manufacture of bars oi special dimensions. This feature is especially valuable and is one not present in the .forms of tension bars now in use, in which the anchor arms radiate'from the center ot' the bar outwardly on either side, the arms beingcentered or balanced towards a common center, instead of being centered or balanced at a series of, local points.

signed to be Apositioned in the concrete structure in the manner mdicated 1n Fig. 1 of the drawings, the mam tension member occupying a position near the lower side of the con crete structure and the anchor arms projecting therefrom o n the side toward the larger body of concrete. -The tensile strains existf ing in the beam will be transmitted to the tension member not only byfthe adhesion of the concrete thereto, but through. the inter locking of the concrete and the tension member, such Ainterlocking resulting from the concrete :filling the openings in the web formed by bending up the anchor arms.

The-principal function of the anchors is to flbond the. whole mass together vertically,

and in case of failure'jand .the consequent s'tripping of the rod from the cement, these anchors will hold said bar to the concrete mass. The anchors' will act as a vertical anchorage of an improved form, and not asv diagonal tension members of a truss formatiomas in other forms of bars.

I claim: ,i

l A reinforce bar or member i or concrete floors and like structures oi an inverted channel form, comprising afp'air of marginal por In use, myv improved tension bar is detioP-.is having flat surfaces, a groove having flaring sides, and a central web rectangular in cross section, portions of tho web being slittod and bent up from opposite directions to form vertical pairs 0f anchor prongs reotangular in cross soot-ion at right angles to the main portion of the bar,

.2. A reinforce bar or inombor for concrete floors and like structures oi an inverted channel form, comprising a 'iair of thickened niarginal portions having flat surfaces, a groove iiaving flaring sides, and a thin central web rectangular in' cross section, portions of tho web boing slitted and bont up from opposite directions to form Vortioal pairs of anchor prongs rectangular in cross section at right angles to theA main portion of tho bar and having and flanges bent outwardly parallel with the flat surface of tho bar or nlmnbor.

3. `A reinforcing member for a oonorvto beam, consisting of a metal bar, a serios of airs of anchor arms nach pair boing iormvd by slitting said bar, `said arms liavingiroo ends and the arms of ear-.l1 of said pairs boing adjacent to oaoh other and spar/0d apart at substantially equal distances longitudinally of the bar.

Signed at Chicago, Illinois, this` (tli day of ,July 1005.

CHARLES E. SPltlNillCltl 

